A wide -angle lens used for projection display

Abstract

The invention provides a non-out-of-focus optical wide-angle lens for projection display, which can achieve no-out-of-focus in a wide temperature range, and at the same time, the projection quality is clear and delicate. The lens mainly includes a first mirror group, a second mirror group and a TIR prism sequentially from the projection screen side to the display chip side, and an aperture stop is arranged between the first mirror group and the second mirror group; the first mirror group and the second mirror group All lenses in the second lens group are divided into two materials: colorless optical glass and colorless optical plastic; the overall refractive power of the first three lenses in the first lens group is negative, and at least one of them is a plastic aspheric lens; At least one of the first four lenses of the second lens group is a plastic aspheric lens, at least some of the other lenses in the first four lenses constitute a cemented lens part, and the refractive power of the cemented lens part is negative; colorless optical glass The refractive index n1 satisfies 1.4<n1<1.95, and the refractive index n2 of the colorless optical plastic satisfies 1.5<n2<1.6.

Description

technical field [0001] The invention relates to an optical lens structure for projection display. Background technique [0002] Under normal circumstances, when projecting a display screen, with the accumulation of internal heat, it will cause thermal defocusing, which is manifested as image blurring. Surface and display devices (such as LCD, LCOS, DMD) will no longer coincide. [0003] There are three common ways to solve this problem: [0004] 1. Manually adjust the lens to visually judge whether it is clear or not; [0005] 2. Send a drive command to the built-in motor of the projector through the remote control to adjust the lens to visually judge whether it is clear or not; [0006] 3. Install a camera on the projector to monitor the clarity of the projection screen in real time. If the image becomes blurred, the software will calculate the amount of lens movement that needs to be adjusted, and then send instructions to drive the motor. The software processes the ca...

AI Technical Summary

Problems solved by technology

[0009] The first solution: manual adjustment, lower customer experience satisfaction

[0010] Scenario 2: The remote control and motor may fail, resulting in a less satisfied customer experience

[0011] The third solution: Compared with the second solution, the reliability is lower, and the camera, software and motor may fail, resulting in lower customer experience satisfaction

However, this solution still has shortcomings, such as a large number of lenses, a large volume of the optical system, high production costs, high installation and maintenance costs, so the market response is not very satisfactory

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